MCP Server Demo

A barebones .NET 10 MCP (Model Context Protocol) server demonstrating how to expose tools for AI assistants like Claude Desktop, Cursor, and VS Code Continue.

Prerequisites

• .NET 10 SDK
• Node.js (for MCP Inspector testing)

Running the Server

cd src/McpServerDemo.WebApi
dotnet run

The server will start on http://localhost:5125 with the SSE endpoint at http://localhost:5125/sse.

Testing

Option 1: MCP Inspector (Browser)

npx @modelcontextprotocol/inspector

Open http://localhost:6274 and connect to http://localhost:5125/sse.

Option 2: MCP Explorer (Windows)

Download from https://mcp-explorer.com and connect to http://localhost:5125/sse.

Client Configuration

Claude Desktop

Edit %APPDATA%\Claude\claude_desktop_config.json:

{
  "mcpServers": {
    "demo-docs": {
      "command": "npx",
      "args": ["mcp-remote", "http://localhost:5125/sse"]
    }
  }
}

Cursor

In Settings → MCP:

{
  "mcpServers": {
    "demo-docs": {
      "url": "http://localhost:5125/sse",
      "transport": "sse"
    }
  }
}

VS Code Continue

Create ~/.continue/mcpServers/demo-docs.yaml:

name: Demo Docs
version: 0.0.1
schema: v1
mcpServers:
  - name: demo-docs
    type: sse
    url: http://localhost:5125/sse

Project Structure

McpServerDemo/
├── McpServerDemo.sln
└── src/
    └── McpServerDemo.WebApi/
        ├── Program.cs              # MCP server configuration
        ├── Tools/
        │   └── SearchDocs.cs       # MCP tool implementation
        ├── Services/
        │   ├── IDocumentSearchService.cs
        │   ├── DocumentSearchService.cs
        │   ├── ILlmService.cs
        │   └── LlmService.cs
        └── Properties/
            └── launchSettings.json

Extending

To add more tools, create a new class in the Tools folder with the [McpServerToolType] attribute and methods decorated with [McpServerTool].

[McpServerToolType]
public class MyNewTool
{
    [McpServerTool]
    [Description("Does something useful")]
    public async Task<string> DoSomething(
        [Description("Input parameter")] string input)
    {
        // Implementation
    }
}

License

MIT